Method for diagnosing faults of power system on the basis of protecting action chain

The invention discloses a method for diagnosing faults of a power system on the basis of a protecting action chain, comprising the following steps of: firstly, establishing a model, including network modeling and protective information modeling; and secondly, diagnosing the faults on the basis of the protecting action chain by alarm information of a power system in a grid dispatching automation system. According to the method, the matching relationship between the protecting action alarm and the action alarm of a circuit breaker, important grades of the protecting action and the effective relationship among protected main equipment associated with the protecting action can be analyzed, a protecting action chain by taking a suspended fault element as a unit can be formed, the fault position of the power system can be diagnosed and quick diagnose result can be analyzed; and meanwhile, since the requirement on the network modeling is not high, the model is convenient for maintenance, in particular in a dispatching system which is more difficult to model and has not high high-grade application degree. The method for diagnosing the faults has low requirement on the network modeling andis quite practical.